When discussing sources of "hidden sugars" with my patients I find that they are often very surprised at my position on orange juice. Essentially, I have taken it off the table. Frequently, the response I get is, "But what about the vitamin C?" The reality of the situation is that yes, a glass of orange juice does indeed contain some vitamin C, but that fact hardly outweighs the fact that O. J. Is just loaded with sugar. A single 12 ounce glass of O. J. Contains an incredible 9 teaspoons of sugar, about the same as a 12 ounce can of Coke! This equates to 36 grams of carbs, about half of what you should consume in a day. Let's do a little math. If a person were to drink just one glass of orange juice each day, that would mean that he or she would be consuming an extra 3, 285 teaspoons (close to 70 cups) of sugar in a year or about 53, 000 extra calories. This likely translates to unwanted weight gain, and as we've just learned from a study published last week, sugar consumption worsens blood pressure and cardiovascular risk markers, even in the absence of weight gain. So if you're concerned about vitamin C, sleep easy knowing that you're probably getting enough in your multivitamin. The cost to your health from the sugar load in a glass of orange juice should justify your decision to opt out. Some days it's tough to get the recommended two servings of fruit. Fresh produce can unexpectedly spoil (although, there's always frozen), our shopping list is often at the mercy of seasonal fruit crops, and you can't exactly peel an orange on the subway on your way to work when you're in a hurry (or at least youshouldn't, because eww). On those days, drinking your fruit in the form of juice seems like an easy substitute. It's quick and convenient, plus it counts as fruit, right? It says "100% fruit juice" right there on the label! Not so fast: Like every other thing in life that's too good to be true, you can't actually make an even swap between real, bonafide fruit and fruit juice (even if it's the organic, non-GMO, fresh-squeezed, no-sugar-added kind). In fact, drinking juice-especially as a replacement for actual fruit-can do more harm than good.. so much so that you might be better off skipping your fruit servings entirely for a day rather than filling your quota with juice. We asked registered dietitians to give us the scoop on fruit juice, and they shared five reasons why you should stop drinking it ASAP. Read on, and for more on how to eat healthy, check out What Happens to Your Body When You Drink Orange Juice. 1 You're not getting any fiber Shutterstock Fruits fall on the list of the healthiest high-fiber foods. In fact, fiber is one of fruit's biggest selling points; it aids your digestion and fills you up so you eat fewer calories overall. When you drink fruit juice, however, you're missing out. "Juice lacks the fiber found in whole fruits and vegetables [because]the juicing process strips fruit and vegetables of their fiber," says Sarah Rueven, MS, RD, founder of Rooted Wellness. "For this reason, I always recommend blending up fruits and vegetables [into smoothies, which] retains their fiber content, or simply grabbing a piece of fruit over a glass of fruit juice." Basically, if you'd rather drink your fruit than eat it, look to smoothies-not juice-to fill you up. For that, try 10 Fat-Burning Smoothie Recipes Nutritionists Always Drink. 2 It tricks your brain Shutterstock Not only does juice lead you to falsely believe you're making a healthy choice (if I can eat a daily serving of fruit, I can drink it, too), it can also make it super easy to over-consume serving sizes. "When you consume an eight-ounce glass of juice, you are drinking the equivalent of about three to five pieces of fruit in just a few gulps," warns registered dietitian Amy Shapiro, MS, RD, founder of Real Nutrition. "Would you sit down to eat four oranges?" Well, when you put it that way.. no! Because so much fruit is used to produce even a single serving of juice, you could easily be consuming triple or quadruple servings. While it's better to over-consume fruit instead of, say, chips or chocolate, fruit isn't a dietary free-for-all. RELATED: Sign up for our newsletter to get daily recipes and food news in your inbox! 3 It's all empty calories Shutterstock Calories are not evil: They're actually a necessity for life, fueling our bodies and giving us the energy to go about our day. But we should choose our calories wisely, or else we risk racking up calories without adding any nutritional benefits to our diet. That's essentially what happens when we drink fruit juice, says Shapiro: "Research shows that our bodies do not process the calories we consume in beverages like juice; therefore, we consume those calories and then we eat food on top of it." In other words, it might not seem like a big deal to drink 150 calories worth of fruit juice, but since it won't give you any real satiety, you're just going to follow it up with more food (i. E. More calories), while rendering the 150 calories you just consumed from the juice mostly useless. 4 It causes your blood sugar to spike Shutterstock Because fruit juice lacks fiber, there isn't anything to offset its natural sugar content; this leads to dramatic spikes in blood sugar. Not only is this bad news for your energy levels, but it's also going to wreak havoc on your cravings, too. "[Juice] can increase blood sugar quickly, leading to a burst of energy followed by a blood sugar crash," says Shapiro, "[which causes] you to either drink more juice-and more sugar and calories-or reach for an additional snack." All of this spiking and crashing basically leads to an endless cycle of sugar and calorie consumption. If you absolutely can't break your juice habit, Shapiro recommends limiting yourself to no more than four ounces of juice per day, and also diluting it with water, ice cubes, or seltzer to quench your thirst but limit the amount of sugar consumed. 5 It can cause weight gain Shutterstock So what does all this extra sugar and calories from drinking juice eventually lead to? You guessed it: Weight gain. According to Rueven, this is thanks in large part to the over-consumption we talked about earlier. Since juice is a concentrated source of sugar and calories-and drinking one cup of apple juice is like consuming the sugar and calories of three whole apples -it's easy to be blissfully unaware of how much you're truly consuming. And that's a recipe for weight gain, if we've ever seen one. "If you consume large quantities of juice regularly, you are getting a lot of added calories and sugar in your diet," Rueven explains. "Over time, this can lead to weight gain or make it difficult for you to lose weight." For the same reason, here are 7 Ways Smoothies Will Make You Gain Weight.